Stock cart

ABSTRACT

In a six-wheel stock cart  10  including a dolly frame  1  having a nesting construction, free casters  2  attached to bottom surfaces of the dolly frame  1  that are near four corners of the dolly frame, a pair of stationary casters  3  attached to a bottom surface of a substantially intermediate portion of the dolly frame, and a dolly plate  4  pivotably attached to a site that is near a rearward end portion of the dolly frame, the stock cart is nested based on operation of the four free casters  2  after a plane defined by lower ends of the stationary casters  3  is positioned above a plane defined by lower ends of the four free casters by pivoting the dolly plate  4  upward. Therefore, the stock cart can be freely nested in a direction of a shorter dimension of the stock cart.

TECHNICAL FIELD

The present invention relates to a high-nesting efficiency stock cartfor use in transporting commodity products contained in cardboard boxesor the like, or storing or retaining commodity products, etc.

BACKGROUND ART

Conventional stock carts, as shown in FIGS. 21(a) and 21(b), are formedby a dolly in which free casters 20 are connected to bottom surfaces offour corner portions of a dolly frame having a generally squaredletter-U frame shape or a generally letter-M frame shape in a plan view,and stationary caster 30A are connected to bottom surfaces of oppositeside portions of a substantially middle portion of the dolly frame, andby a pair of movable side face frames detachably connected to forwardand rearward portions of the dolly (not shown in the drawings). To putsuch dollies into a nested state for their storage and retention, thenesting thereof is accomplished in a direction of the length of thedollies due to the unidirectionality of the stationary casters.

However, this fashion of nesting needs a great space in the lengthwisedirection, and therefore has a problem in efficient use of space.

Hence, an object of the invention is to provide a stock cart capable ofbeing nested in a direction of a shorter dimension of the stock cart.

DISCLOSURE OF THE INVENTION

Accordingly, the invention (1) provides a stock cart including a dollyframe having a nesting construction, free casters attached to bottomsurfaces of the dolly frame that are near four corners of the dollyframe, a stationary caster attached to a bottom surface of asubstantially intermediate portion of the dolly frame, and a dolly platepivotably attached to a site that is near a rearward end portion of thedolly frame, wherein the stock cart is nested based on operation of thefour free casters after a plane defined by a lower end of the stationarycaster is positioned above a plane defined by lower ends of the fourfree casters by pivoting the dolly plate upward.

Furthermore, the invention (2) provides a stock cart comprising: a dollyframe formed into a generally letter-Z configuration or a generallyreversed letter-Z configuration by a support bar that is disposed at arearward end portion and that has at two ends thereof tubular cylinderportions, a member that is disposed at a forward end portion and isdisposed at a predetermined interval apart from the support bar andparallel to the support bar, and a connector member that integrallyinterconnects an end portion of the member of the forward end portionand an end portion of the support bar of the rearward end portion thatare positioned on a diagonal line; forward end portion-side free castersattached to a bottom surface of the member of the forward end portion ofthe dolly frame; a free caster portion including rearward endportion-side free casters, a free caster support plate that secures andinterconnects support brackets of the rearward end portion-side freecasters, and a pair of piston portions that are secured above the freecasters and that are inserted in the tubular cylinder portions so thatthe piston portions are slidable in upward and downward directions; astationary caster attached to a bottom surface of a middle portion ofthe connector member; a forward end-side side face frame secured at twoends thereof to an end portion of the member of the forward end portion;a rearward end-side side face frame two end portions of which aresecured to or detachably disposed on outer sides of the cylinderportions; and a dolly plate having a rectangular dolly plate body, and apivotal contact portion that is pivotably supported by the support barof the rearward end portion, the stock cart being characterized in thatthe pivotal contact portion of the dolly plate has a support bar bearinggroove, and a plate stopper end portion having a quadrangular section,and a configuration of the dolly plate stopper end portion is formed sothat when the dolly plate is placed on the dolly frame, a distancebetween the support bar and a rearward end surface of the dolly plate isgreater than a distance between the support bar and the free castersupport plate.

Furthermore, the invention (3) provides a stock cart comprising: a dollyframe formed into a generally letter-Z configuration or a generallyreversed letter-Z configuration by a support bar that is disposed at arearward end portion and that has at two ends thereof tubular cylinderportions, a member that is disposed at a forward end portion and isdisposed at a predetermined interval apart from the support bar andparallel to the support bar, and a connector member that integrallyinterconnects an end portion of the member of the forward end portionand an end portion of the support bar of the rearward end portion thatare positioned on a diagonal line; forward end portion-side free castersattached to a bottom surface of the member of the forward end portion ofthe dolly frame; a free caster portion including rearward endportion-side free casters, a free caster support member that secures andinterconnects support brackets of the rearward end portion-side freecasters, and a pair of piston portions that are secured above the freecasters and that are inserted in the tubular cylinder portions so thatthe piston portions are slidable in upward and downward directions; astationary caster attached to a bottom surface of a middle portion ofthe connector member; a forward end-side side face frame secured at twoends thereof to an end portion of the member of the forward end portion;a rearward end-side side face frame two end portions of which aresecured to or detachably disposed on outer sides of the cylinderportions; and a dolly plate having a rectangular dolly plate body, and apivotal contact portion that is pivotably supported by the support barof the rearward end portion, the stock cart being characterized in thata support bar bearing groove is formed on a lower surface side of thepivotal contact portion, and a stopper piece is formed on an uppersurface of the pivotal contact portion, and the dolly plate is connectedto the rearward end-side side face frame so that a plane defined by alower end of the stationary caster is above a plane defined by lowerends of the four free casters by bringing the stopper piece and the freecaster support member into contact.

Furthermore, the invention (4) provides a stock cart wherein the dollyframe is formed into a generally letter-H configuration by a support barthat is disposed at a rearward end portion and that has at two endsthereof tubular cylinder portions, a member that is disposed at aforward end portion and is disposed at a predetermined interval apartfrom the support bar and parallel to the support bar, and a connectormember that integrally interconnects a middle portion of the member ofthe forward end portion and a middle portion of the support bar of therearward end portion that are positioned on a center line of the memberof the forward end portion and the support bar of the rearward endportion.

Furthermore, the invention (5) provides a stock cart comprising: a dollyframe formed into a generally letter-H configuration by a member that isdisposed at a rearward end portion and that has in a middle portionthereof a hole extending upward and rearward through the member, amember that is disposed at a forward end portion and is disposed at apredetermined interval apart from the member of the rearward end portionand parallel to the member of the rearward end portion, and a connectormember that integrally interconnects a middle portion of the member ofthe forward end portion and a middle portion of the member of therearward end portion that are positioned on a center line of the memberof the forward end portion and the member of the rearward end portion;forward end portion-side free casters attached to a bottom surface ofthe member of the forward end portion of the dolly frame; a free casterportion including rearward end portion-side free casters, a free castersupport member that secures and interconnects support brackets of therearward end portion-side free casters, a support column portionstanding from an upper surface of the free caster support member, and asupport bar extending perpendicularly across a distal end of the supportcolumn portion and having a pair of right and left support shafts, thesupport column portion loosely fitted in a hole of the member of therearward end portion of the dolly frame so that the support columnportion and the member of the rearward end portion are movable relativeto each other in upward and downward directions; a stationary casterattached to a bottom surface of a middle portion of the connectormember; a forward end-side side face frame secured to the member of theforward end portion; a rearward end-side side face frame secured to aside face frame holder portion that has a shaft-like protrusion and thatis coupled to the member of the rearward end portion; and a dolly platehaving a rectangular dolly plate body that is connected at a rearwardend portion-side end portion thereof with a pair of pivotal connectorplates that are pivotably supported by a support shaft of the supportbar and the shaft-like protrusions attached to the side face frameholder portion, the stock cart being characterized in that the dollyplate is connected to the rearward end-side side face frame so that bypivoting the dolly plate with a support portion of the shaft-likeprotrusion serving as a fulcrum, the support column portion is spacedapart from the member of the rearward end portion of the dolly frame,and a plane defined by a lower end of the stationary caster ispositioned above a plane defined by lower ends of the four free casters.

Furthermore, the invention (6) provides a stock cart, wherein the dollyframe is formed into a generally letter-Z configuration or a generallyreversed letter-Z configuration by a member that is disposed at arearward end portion and that has in a middle portion thereof a holeextending upward and rearward through the member, a member that isdisposed at a forward end portion and is disposed at a predeterminedinterval apart from the member of the rearward end portion and parallelto the member of the rearward end portion, and a connector member thatintegrally interconnects an end portion of the member of the forward endportion and an end portion of the member of the rearward end portionthat are positioned on a diagonal line.

Furthermore, the invention (7) provides a stock cart wherein in a movingstate, the stock cart becomes a six-wheel cart, and can be moved in afashion of a seesaw with the middle-positioned stationary caster being acenter, and can be freely turned in direction, and when the stock cartis to be nested, the dolly plate is stood up so that a ground contactplane defined by a lower end of the stationary caster is positionedabove a plane defined by lower ends of the free casters and, thus, thestationary caster does not contact a ground surface but becomes idle,and the stock cart is movable only on the four free casters.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a stock cart of the invention,illustrating an overall construction thereof.

FIG. 2 is an enlarged view of a rearward end portion shown in FIG. 1.

FIG. 3 is an exploded view of main portions of the stock cart of theinvention.

FIG. 4 is a perspective view illustrating a state where a dolly plate isstood up.

FIG. 5 is an enlarged view of a rearward end portion shown in FIG. 4.

FIG. 6 are views illustrating states of contact between a pivotalcontact portion of the dolly plate and a free caster support plate.

FIG. 7 is a side view of the stock cart where the dolly plate is laiddown.

FIG. 8 is a side view of the stock cart where the dolly plate is stoodup.

FIG. 9 is a view illustrating a state of contact between a pivotalcontact portion of a dolly plate and a free caster support plate inanother form.

FIG. 10 is an illustration of a state of contact between a pivotalcontact portion of a dolly plate and a free caster support plate instill another form.

FIG. 11 is a perspective view illustrating a state in which a dollyplate of a stock cart of the invention is stood up.

FIG. 12 is a perspective view illustrating a state in which the dollyplate of the stock cart of the invention is laid down.

FIG. 13 is an enlarged view of a rearward end portion shown in FIG. 12.

FIG. 14 is a side view thereof, a portion of which shows an A—A sectionindicated in FIG. 13.

FIG. 15 is an enlarged view of a rearward end portion shown in FIG. 11.

FIG. 16 is a side view thereof, a portion of which shows a B—B sectionindicated in FIG. 15.

FIG. 17 is a side view of a downward portion shown in FIG. 12, where aportion is omitted.

FIG. 18 is a side view of a downward portion shown in FIG. 11, where aportion is omitted.

FIG. 19 is a plan view illustrating a nested state in a case where eachdolly frame has an H-shaped configuration.

FIG. 20 is a plane view illustrating a state where effective nesting isnot possible,

FIG. 21 are illustrations of nested states of conventional stock carts.

DETAILED DESCRIPTION

An embodiment of the invention will be described hereinafter withreference to FIG. 1 to FIG. 9. FIG. 1 is a perspective view of a stockcart of the invention; FIG. 2 is an enlarged view of a rearward endportion shown in FIG. 1; FIG. 3 is an exploded view of main portions;FIG. 4 is a perspective view illustrating a state where a dolly plateshown in FIG. 1 is stood up; FIG. 5 is an enlarged view of a rearwardend portion shown in FIG. 4; FIG. 6(a) is a view taken along line A—A inFIG. 2; FIG. 6(b) is a view taken along line B—B in FIG. 5; FIG. 7 is aside view where the dolly plate is laid down; and FIG. 8 is a side viewwhere the dolly plate is stood up. In FIG. 1 to FIG. 8, a stock cart 10has a caster-equipped dolly frame 1, a pair of side face frames 5, 5,and a dolly plate 4.

As shown in FIG. 3, the dolly frame 1 is formed into a letter-Zconfiguration by a support bar 52 that has, at its two ends, tubularrectangular-prismatic cylinder portions 51 a, 51 b, and a forward endmember 101 that is disposed at a predetermined interval apart from thesupport bar 52 and parallel thereto, and a connector member 202 thatintegrally interconnects diagonally-positioned end portions of theforward end member 101 and the rearward end support bar 52. Free casters2, 2 are attached to a bottom surface of the member 101 disposed at theforward end portion of the dolly frame 1. Piston portions 23, 23 of afree caster portion 2A are inserted into bottom surfaces of the cylinderportions 51 a, 5 b in such a manner that the piston portions 23, 23 areslidable in upward and downward directions. Stationary casters 3, 3 areattached to a bottom surface of a middle portion of the connector member202 via a stationary caster support plate 7 and a stationary casterheight adjuster plate 71. The side face frame 5 b is formed by fixingtwo ends thereof to end portions of the member 101, and the side faceframe 5 a is formed by fixing two end portions thereof to outer sides ofthe cylinder portions 51 a, 51 b.

The dolly plate 4 is formed by a pivotal contact portion 42 pivotablysupported to the support bar 52, a rectangular dolly plate body 41, anda dolly plate height adjuster plate 49. The dolly plate height adjusterplate 49 is a pair of box-like members formed on both sides of a middleportion of a reverse surface of the dolly plate body 41. The pivotalcontact portion 42 is formed by a support bar bearing groove 421, and adolly plate stopper end portion 422 having a quadrangular or rectangularsectional shape. The pivotal contact portion 42 has a shape wherein endportions are cut out to avoid impingement with the cylinder portions 51a, 51 b when the dolly plate 4 is pivoted.

The free caster portion 2A, positioned on the bottom surface of arearward end portion of the dolly frame 1, is formed by the free casters2, 2, a free caster support plate 221 that secures and interconnectssupport blackest 22, 22 of the free casters 2, 2 and that has aconsistent height in a middle portion thereof, and the pair of pistonportions 23, 23 having, on their upper surfaces, sliding portions 231.The connection between the free casters 2, 2 and the piston portions 23,23 is accomplished by screw engagement between male threads of upperportions of the free casters 2, 2 and female threads formed inside thepiston portions 23. The piston portions 23, 23 of the free casterportion 2A formed as described above are inserted into the pair ofcylinder portions 51 a, 51 b from below to form a stock cart.

When the stock cart 10 of the embodiment constructed as described aboveis to be used, the dolly plate 4 pivotable about the support bar 52positioned at the rearward end portion is laid down onto the frame 1.The dolly plate height adjuster plate 49 contacts the stationary castersupport plate 7, so that the dolly plate 4 assumes a stable state wherethe dolly plate 4 is parallel to a ground surface. Furthermore, withregard to the rearward end portion of the dolly plate 4, a rearwardreverse surface 45 of the dolly plate contacts an upper surface of thefree caster support plate 221 as shown in FIG. 6(a).

The thus-formed stock cart 10 is a six-wheel cart as shown in FIG. 1 andFIG. 7. The stock cart 10 can be moved in the fashion of a seesaw withthe middle-positioned stationary casters 3, 3 being a center.Furthermore, direction turning movements and the like of the stock cart10 can be freely accomplished. The dolly plate 4 may be simply placed onthe dolly frame 1, or may be fastened thereto by a fastening device.Ground contact planes X—X defined by ground-surface contact points ofthe free casters 2, 2, 2, 2 and the stationary casters 3, 3 may be oneand the same plane, or the ground contact plane defined by the points ofcontact of the stationary casters 3, 3 with a ground surface may bebelow the ground contact plane defined by the points of contact of thefree casters 2, 2, 2, 2 with a ground surface.

Next, when the stock cart 10 is to be nested, a forward end-side endportion 401 of the dolly plate 4 is lifted upward, and the dolly plate 4is stood up by pivoting the dolly plate 4 about the support bar 52positioned at the rearward end portion. The dolly plate 4 is thensecured to the side face frame 5 a formed rearward by, for example, achain or a rope, although not shown in the drawings.

As shown in FIG. 5 and FIGS. 6(a) and 6(b), because a distance b betweena center of the support bar 52 and an end surface of the dolly plate isgreater than a distance a between the center of the support bar 52 andthe reverse surface of the dolly plate, and because the piston portions23 a, 23 b of the free casters are slidable in the upward and downwarddirections within the cylinder portions 51 a, 51 b, the standing of thedolly plate 4 replaces the contact between the upper surface of the freecaster support plate 221 and the rearward reverse surface 45 of thedolly plate with the contact between the upper surface of the freecaster support plate 221 and the rearward end surface 46 of the dollyplate, so that the support bar 52 is lifted upward. That is, thestationary casters 3, 3, the side face frame 5 a and the integrallyconnected members of the dolly frame 1 are lifted by amountscorresponding to a length H from the state assumed during the use, sothat a ground contact plane defined by lower ends of the stationarycasters 3, 3 is positioned above the plane defined by the lower ends ofthe free casters 2, 2, 2, 2, as shown in FIG. 8. In this case, a framebody formed by the side face frames 5 a, 5 b and the dolly frame assumesa state where the frame body is slightly inclined rightward (toward theforward end portion).

In the nestable-state cart, the stationary casters 3, 3 do not contactthe ground surface, so that the wheels are idle, and the cart is movedonly on the four free casters. Therefore, the cart can be moved in freedirections, and can be nested in a direction of a shorter dimension ofthe cart. Thus, it becomes possible to perform a nesting operation in alimited space.

Furthermore, in the invention, the dolly frame is not restricted by theabove-described letter-Z configuration as long as the dolly frame has anesting construction. For example, a letter-H configuration, a reversedletter-Z configuration, and the like may be adopted.

Furthermore, in the invention, the pivotal contact portion of the dollyplate and the free caster support plate are not particularly limited aslong as the pivotal contact portion and the free caster support plateperform an operation of raising the stationary casters and an integralportion of the dolly frame (in a view from the dolly frame, an operationof lowering the free caster portion 2A) at the time of pivoting thedolly plate upward. For example, a method as shown in FIG. 9 based onthe contact between a crank-shaped metal plate 47 formed on a dollyplate 4 and a member 225 attached to a free caster support plate, amethod as shown in FIG. 10 based on the contact between an elongatedhole 49 a formed in a protruded portion 48 protruded upward at 45° froman edge of a dolly plate 4 and a member 225 attached to a free castersupport plate, or the like maybe cited. In either method, the dollyframe is lifted by an amount corresponding to a length H in a statewhere the dolly plate 4 is stood up (portion (b) in each drawing) incomparison with a state where the dolly plate 4 is laid down (portion(a) in each drawing).

Next, a second embodiment of the invention will be described withreference to FIG. 11 to FIG. 20. In FIG. 11 to FIG. 18, a stock cart 10Ahas a caster-equipped dolly frame 1, a pair of side face frames 5 a, 5b, and a dolly plate 4.

The dolly frame 1 is formed into a letter-H configuration by a member101 a at a forward end portion and a member 101 b at a rearward endportion that are spaced from each other by a predetermined interval andare disposed parallel to each other, and by a connector member 202 thatintegrally interconnects the two end members 101 a, 101 b. Free casters2, 2 are attached to a bottom surface of the member 101 a disposed atthe forward end portion of the dolly frame 1. A brake operating means 50and a nesting restricting protrusion 70 are provided on an upper surfaceof the member 101 a. Impact absorber pads 60, 60 are provided on an endsurface portion of the member 101 a. The member 101 b disposed at therearward end portion of the dolly frame 1 has a bottomless lid shape.The member 101 b has, in an upper surface of a middle portion thereof, athrough-hole 102 that loosely fits over a support column portion 31 of acaster support 30. The member 101 b has, in a lower surface of thelid-like shape thereof, engaging protruded rods 103, 103 that areslidably inserted into guide cylinder-like portions 32, 32 provided onthe caster support 30. As in the member 101 a of the forward endportion, the member 101 b is provided, on its upper surface, with anesting restricting protrusion 70, and is provided, on its end surfaceportion, impact absorber pads 60.

Two end portions of the connector member 202 are provided with side faceframe holder portions 40, 40 each of which is secured at one end thereofto the member 101 a or 101 b. The side face frames 5 a, 5 b can beformed by inserting support columns of the side face frames 5 a, 5 binto the side face frame holder portions 40, 40. The caster support 30has a channel-like shape. The free casters 2, 2 are attached to two endsof a lower surface of the caster support 30. The support column portion31, which is positioned at a middle of the caster support 30 and extendsupward therefrom, has in its distal end portion a shaft support portion311 that pivotably bears or secures a support bar 81. Stationary casters3, 3 are attached to a bottom surface of a middle portion of theconnector member 202 via a stationary caster support plate 7 and astationary caster height adjuster plate 71.

The dolly plate 4 is formed by two pivotal connector plates 58, 58pivotably supported to the support bar 81 and shaft-like protrusions551, 551 attached to the side face frame 5 b, a rectangular dolly platebody 41A, and dolly plate height adjuster plates 59. Each pivotalconnector plate 58 is formed by a support bar bearing portion 521located at a distal end of the pivotal connector plate 58, a shaft-likeprotrusion bearing portion 522, and a dolly plate stopper portion 423.The shaft-like protrusion bearing portion 522 of each pivotal connectorplate 58 serves as a fulcrum for the pivoting of the dolly plate 4, andis positioned diagonally downward from the support bar bearing portion521. Due to this construction, when the dolly plate 4 is stood up, thesupport bar bearing portions 521 of the pivotal connector plates 58, 58are forced downward, with the shaft-like protrusion bearing portions 522serving as a fulcrum, so that the caster support 30 is forced downwardrelative to the dolly frame 1. The positions of disposal of theshaft-like protrusions 551, 551 and the shaft-like protrusion bearingportions 522 may be contrary to what is described above. That is, theshaft-like protrusions 551, 551 may be secured to the pivotal connectorplates 58, 58, and the shaft-like protrusion bearing portions 522 may besecured to the side face frame 5 b.

The shape of the side face frame 5 b is generally rectangular. Anesting-side vertical member 501 of the side face frame 5 b has areceded portion 502 and a receded portion 503 for, at the time ofnesting, avoiding overlaps with the dolly plate height adjuster plates59 of an adjacent stocker cart and thereby avoiding formation of uselessspaces. When the stock cart 10A of the embodiment constructed asdescribed above is to be used, the dolly plate 4 pivotable about theshaft-like protrusions 551, 551 secured to lower portions of the sideface frame 5 b is laid down onto the dolly frame 1 (FIG. 12 to FIG. 14and FIG. 17). The dolly plate height adjuster plates 59 contact thestationary caster support plate 7, so that the dolly plate 4 assumes astable state where the dolly plate 4 is parallel to a ground surface.Furthermore, with regard to the rearward end portion of the dolly plate4, a rearward reverse surface 45 of the dolly plate contacts an uppersurface of the member 101 b disposed at the rearward end portion.

The thus-formed stock cart 10A is a six-wheel cart as shown in FIG. 12and FIG. 17. The stock cart 10A can be moved in the fashion of a seesawwith the middle-positioned stationary casters 3, 3 being a center.Furthermore, direction turning movements and the like of the stock cart10A can be freely accomplished. The dolly plate 4 may be simply placedon the dolly frame 1, or may be fastened thereto by a fastening device.Ground contact planes X—X of the free casters 2 and the stationarycasters 3 may be one and the same plane, or the ground contact plane ofthe stationary casters 3 may be below the ground contact plane of thefree casters 2.

Next, when the stock cart 10A is to be nested, the dolly plate 4 isstood up by pivoting the dolly plate 4. The dolly plate 4 is thensecured to the side face frame 5 b formed rearward by, for example, achain or a rope, although not shown in the drawings.

In the stock cart 10A of this embodiment, each pivotal connector plate58 connected to the dolly plate 4 has the support bar bearing portion521 and the shaft-like protrusion bearing portion 522, and theshaft-like protrusion bearing portion 522 is positioned diagonallydownward of the support bar bearing portion 521, and serves as the pivotfulcrum of the dolly plate 4, as shown in FIG. 13 to FIG. 18. Therefore,by standing the dolly plate 4 up, the side face frame 5 b is liftedupward. That is, the stationary casters 3, the side face frame 5 b andthe integrally secured members of the dolly frame 1 are lifted byamounts corresponding to a length H from the state assumed during theuse, so that a plane defined by lower ends of the stationary casters 3is positioned above the plane defined by the lower ends of the freecasters 2, as shown in FIG. 18. In this case, a frame body formed by theside face frames 5 a, 5 b and the dolly frame assumes a state where theframe body is slightly inclined rightward (toward the forward endportion). In this nestable-state cart, the stationary casters 3 areidle, and the cart is moved only on the four free casters. Therefore,the cart can be moved in free directions, and can be nested in adirection of a shorter dimension of the cart.

The nesting will be described with reference to FIG. 19 and FIG. 20.FIG. 19 is a plan view illustrating a nested state in a case where eachdolly frame has an H-shaped configuration; and FIG. 20 is a plan viewillustrating a state where effective nesting is not possible. In FIG.19, in the case where each dolly frame has the H-shaped configuration,the nesting restricting protrusion 70 restricts the direction ofnesting, and thus indicates a correct direction to an operating person.That is, if the nesting is performed on the nesting restrictingprotrusion 70-located side, space can be efficiently used withoutforming a useless space. If the nesting is attempted on the sideopposite to the nesting restricting protrusion 70-located side, thenesting restricting protrusion 70 and the connector member 202 of dollyframes impinge on each other, so that effective nesting is notaccomplished. In contrast, in the case where a nesting restrictingprotrusion 70 is not provided as shown in FIG. 20, an operating personbecomes confused in determining a nesting direction. For example, if thenesting of a stock cart group 90 and a stock cart group 91 together isattempted, the forward end members 101 a of dolly frames 1 contact eachother and the rearward end members 101 b contact each other, so that auseless space is formed. If each dolly frame 1 has a Z-shapedconfiguration or a reversed Z-shaped configuration, the nestingdirection is relatively readily determined. Therefore, the nestingrestricting protrusion 70 is effective particularly if the dolly frame 1has an H-shaped configuration.

Furthermore, in the invention, the function or structure of the pivotalportion of the dolly plate is not limited to the above-describedfashions but may be provided in various forms, as long as the pivotalportion performs an operation of raising the stationary casters and anintegral portion of the dolly frame (in a view from the free casters, alowering operation) at the time of pivoting the dolly plate upward.

According to the invention, when the stock cart is to be used, the dollyplate is laid down, and loads are placed thereon, and the stock cart ismoved. The stock cart can be moved in a seesaw fashion about thestationary casters, and the direction turning and the like of the stockcart can be freely performed. When the stock cart is to be stored, thatis, when the stock cart is to be nested, the dolly plate is stood up, sothat the stationary casters become idle. That is, the stock cart ismovable only on the four free casters, so that the stock cart can bemoved in free directions, and can be nested in a direction of a shorterdimension of the stock cart. Furthermore, at the time of nesting, anerror in the nesting direction is eliminated, so that the operatingefficiency improves and space can be efficiently used without forming auseless space.

What is claimed is:
 1. A stock cart comprising: a dolly frame formedinto a generally letter-Z configuration or a generally reversed letter-Zconfiguration by a support bar that is disposed at a rearward endportion and that has at two ends thereof tubular cylinder portions, amember that is disposed at a forward end portion and is disposed at apredetermined interval apart from the support bar and parallel to thesupport bar, and a connector member that integrally interconnects an endportion of the member of the forward end portion and an end portion ofthe support bar of the rearward end portion that are positioned on adiagonal line; forward end portion-side free casters attached to abottom surface of the member of the forward end portion of the dollyframe; a free caster portion including rearward end portion-side freecasters, a free caster support plate that secures and interconnectssupport brackets of the rearward end portion-side free casters, and apair of piston portions that are secured above the free casters and thatare inserted in the tubular cylinder portions so that the pistonportions are slidable in upward and downward directions; a stationarycaster attached to a bottom surface of a middle portion of the connectormember; a forward end-side side face frame secured at two ends thereofto an end portion of the member of the forward end portion; a rearwardend-side side face frame two end portions of which are secured to ordetachably disposed on outer sides of the cylinder portions; and a dollyplate having a rectangular dolly plate body, and a pivotal contactportion that is pivotably supported by the support bar of the rearwardend portion, the stock cart being characterized in that the pivotalcontact portion of the dolly plate has a support bar bearing groove, anda plate stopper end portion having a quadrangular section, and aconfiguration of the dolly plate stopper end portion is formed so thatwhen the dolly plate is placed on the dolly frame, a distance betweenthe support bar and a rearward end surface of the dolly plate is greaterthan a distance between the support bar and the free caster supportplate.
 2. A stock cart comprising: a dolly frame formed into a generallyletter-Z configuration or a generally reversed letter-Z configuration bya support bar that is disposed at a rearward end portion and that has attwo ends thereof tubular cylinder portions, a member that is disposed ata forward end portion and is disposed at a predetermined interval apartfrom the support bar and parallel to the support bar, and a connectormember that integrally interconnects an end portion of the member of theforward end portion and an end portion of the support bar of therearward end portion that are positioned on a diagonal line; forward endportion-side free casters attached to a bottom surface of the member ofthe forward end portion of the dolly frame; a free caster portionincluding rearward end portion-side free casters, a free caster supportmember that secures and interconnects support brackets of the rearwardend portion-side free casters, and a pair of piston portions that aresecured above the free casters and that are inserted in the tubularcylinder portions so that the piston portions are slidable in upward anddownward directions; a stationary caster attached to a bottom surface ofa middle portion of the connector member; a forward end-side side faceframe secured at two ends thereof to an end portion of the member of theforward end portion; a rearward end-side side face frame two endportions of which are secured to or detachably disposed on outer sidesof the cylinder portions; and a dolly plate having a rectangular dollyplate body, and a pivotal contact portion that is pivotably supported bythe support bar of the rearward end portion, the stock cart beingcharacterized in that a support bar bearing groove is formed on a lowersurface side of the pivotal contact portion, and a stopper piece isformed on an upper surface of the pivotal contact portion, and the dollyplate is connected to the rearward end-side side face frame so that aplane defined by a lower end of the stationary caster is above a planedefined by lower ends of the four free casters by bringing the stopperpiece and the free caster support into contact.